[DobsOnly]

Assembling my first cMoy. Have succesfully installed and tested the Power Supply section. Basic cMoy with 470uf Electrolytic Caps.

My Question is I have purchased several different caps for the inputs.

.1uf Digi-Key 100v Metal film box (small blue box).
.22uf Newark Metallized Polyester, 40vac (white box casing).
470nf Newark Metalized Polyester, (white box casing).

Which of these caps would be the best choice?

Also with Ety 6er ear phones are there any other tweaks I should consider while assembling or is the default biasing OK?


I had no idea until I got started how intricate this work is. Past soldering practice was with RC Cars and Planes. I'm so glad I got a Soldering station and pencil with a nice small tip for this stuff. It's made a difficult job a lot easier.

Thanks ahead of time for your input.

DobsOnly

 

[Wyloch]

Don't bother with input caps. I don't use them and I've got no problems. But then, I'm running purely off of batteries with both my amp and cd player. If that's not the case for you and you absolutely must use input caps, use the bigger ones.

 

[Tomo]

Hi,

I would use anything bigger than 0.1uF. In my opinion, having input cap is pretty important. The negative side to having cap is that the sound MAY get perturbed. The positive side is that your headphones ain't gonna BLOW.

I used to be a purist, but I am beginning to reconsider. The advent of technology for last few years have been quite significant for caps. I have an ELECTROYTICS in the place of the input cap in my amp with negligible effect.

Lastly, stay away from Polyester. They are cheap and probably worst film caps you can get your hands on. I would go with polypropylenes, but careful with sizes. WIMA makes real tiny ones. (By the way, that's the reason why in the original Chu Moy article, the author chooses 0.1uF. If you make it 1uF, the cap would dwarf the amp. ... Not that I mind.)

T

 

[miketriple]

bigger value is better.. check the specs and make sure that the physical size is going to allow it to fit in your amp's case, like in an altoids tin. many won't.

.22uf or .47uf should be pretty good for input caps. get polyprop, though, not polyester.

a nice station must be nice.. i want to go get a tiny iron tip soon. i made a mint last week with my iron's tip, which is basically concave.. the opposite of a tip. and freakin huge compared to the pins on the so8 chips.

edit: also, with er6is, the impedance is very low. you can easily lower your gain from 11 to 5 or 6. are you using a volume pot? with my shures and my mint at a default of 11 gain, the volume pot was very hard to adjust.. it was too easy to make it way too loud. the er6is have even lower impedance, but the er6s have higher.. i dont know which you have, but either way, it's pretty low..

 

[Vadi]

Epcos makes small polypropylen caps too.

 

[DobsOnly]

Quote:

Originally Posted by miketriple a nice station must be nice.. i want to go get a tiny iron tip soon. i made a mint last week with my iron's tip, which is basically concave.. the opposite of a tip. and freakin huge compared to the pins on the so8 chips.

I got the CSI Station 1. $35. Looks Like a Hakko 936. Works really well for me without the higher price tag.

As for the caps I guess I'll use the .1uf Polypropylene. If I'm understanding this right the small Polypropylene would be better than the larger Polyester Caps. I'll track down some larger Polypropylene caps locally if I can. Can't see paying shipping on a few caps. Anyone know of an electronic supply store in the N.E. Florida, Jacksonville area?

Thanks for everyones input!

DobsOnly

 

[Chef Medeski]

Here is anice little page/essay about the subject. I hope it helps. Input Caps